How Can I get my passport and medical check notarized & attested from chinese embassy in riyadh?

Yes, documents will be used in China should be notarized by Chinese embassy. But make sure the notarial certificate shall be legalized first by the Ministry of Foreign Affairs of your country or its authorized organ, and then legalized by the Chinese Embassy before it is produced in China. Complete a legalization application form before submitting your documents, submit the original document authenticated and its complete duplicate, your passport and the photocopies are required. You can do it in person or by someone entrusted.